Plows of the type disclosed herein having an elongated vertical blade have been utilized for several years to lay cable, flexible pipe, etc. The cable or pipe may either be pulled through the cut of the plow blade or a cable chute may be provided on the trailing edge of the blade which guides the cable into the ground from a drum mounted on the prime mover. More recently, various types of vibrators have been mounted on the plow blade or the supporting frame which effectively reduces the drawbar pull or force required to pull the blade through the ground, such as disclosed in U.S. Pat. No. 3,363,423. Vibration of the blade of a cable laying plow results in several advantages including less ground disturbance, faster cable laying installation, etc.
Following the development of vibratory cable laying plows, several improvements have been made, particularly relating to isolation of the vibrating blade. For example, U.S. Pat. No. 3,618,237 discloses a frame support for a cable laying plow having torque cushioning elements which absorb the reciprocable motion of the support and substantially isolate the frame from the supporting structure. While it is desirable that the vibrator be isolated from the tractor or prime mover, these torque cushioning elements add significantly to the expense and complexity of the frame support.
The vibratory cable plow suspension of the present invention provides a relatively simple and inexpensive support for the vibratory blade and eliminates the requirement for torque cushioning elements to isolate the vibrator from the prime mover.